The present invention relates to a lenticular lens medium including a plurality of semicylindrical-shaped or arc-shaped elongated convex parts, and particularly relates to a lenticular lens medium having a surface on which a toner image can be formed using an electrophotographic printing apparatus.
Various printing systems have been proposed for printing apparatuses which perform printing on printing media of, for example, papers, label sheets, envelopes or OHP sheets. For example, there have been proposed wire dot systems, thermal printing systems, thermal transferring systems, ink jet systems, electrophotographic systems or the like. These systems have been put to practical use. Among these systems, printing apparatuses using the electrophotographic systems (i.e., electrophotographic printing apparatuses) can print images with high density and high quality at high-speed. Therefore, the electrophotographic printing apparatuses have been broadly used and commercialized as output terminals of information processing systems of, for example, copiers, facsimile machines, complex machines having functions of copiers and facsimile machines and scanners.
In addition, there is an increasing interest toward image processing of 3-dimensional image such as 3-dimensional computer graphics or virtual reality along with recent popularization of personal computers and improvement in their performance. Therefore, it is strongly desired for 3-dimensional image forming system using computer to visualize and print 3-dimensional image synthesized in the computer.
A conventional lenticular lens includes a plurality of substantially semicylindrical-shaped lenses (hereinafter referred to as linear convex lenses) having specific lens radii arranged with certain pitches, and includes a flat surface on the backside of the linear convex lenses. The lenticular lens is composed of a transparent resin material and has a certain thickness. The lenticular lens can be used as a printing medium. A group of strip-shaped images corresponding to the linear convex lenses are converted into left-right reversed image and printed on the flat surface of the lenticular lens so that an erect image is viewed from the linear convex lenses side. By changing an angle at which the lenticular lens is viewed (from the linear convex lenses side), or by changing an inclination of the lenticular lens, various kinds of stereoscopic image or moving image can be viewed. In this regard, there is known a lenticular lens medium having a back surface on which a printing is performed using ink jet printing system (see Japanese Laid-Open Patent Publication H09-15766).
However, the conventional lenticular lens medium is generally composed of synthetic resin (such as plastic) or the like which is an insulating body having no electrical conductivity. Therefore, when the electrophotographic printing apparatus is used to perform printing on the lenticular lens medium, toner is not transferred from a photosensitive body to the lenticular lens medium in a transferring process, and therefore a sufficient printing density can not be obtained. Furthermore, in a fixing process in which the toner image (having been transferred to the lenticular lens medium in the transferring process) is thermally fixed to the lenticular lens medium, the lenticular lens medium may be rippled, deformed or warped due to heat. As a result, the printing medium providing excellent printing quality can not be obtained.